First off, I agree Bronx does not hold the same weight if they lose their elephants.
My problem with elephant "sanctuaries" is not only that they take away from the captive gene pool if they are old enough to breed, but also they have an anthropomorfic mind set when taking care of them. One of these "sanctuaries" wouldn't euthanize one of their ele's after it went down and didn't get up for days. Remember, they are animals and not people. The idea of "retiring" them does not benefit the ele. It would be healthier for the animal to be "working". It keeps them in shape and they have longer lives (circus and working animals easily get into their 50's+ because of this reason). I also don't like sanctuaries because they are private and do not provide people the opportunity to see and appreciate these animals. Nothing grabs a persons attention and makes them care about a species like showing them a 6 ton male or letting them interact with a 53 year old female. Trust me, I see it every week. How are you going to get people to invest time and energy to conserving ele's if you don't even see them? I could go on and on but I digress.
Sadly, if you look at the rate in which elephants in Asia and African are being killed and encroached on we are looking at complete extinction of both species in a couple of decades. Even now there are not true wild elephants left. They are managed in national parks and preserves which still doesn't guarantee protection because of culling and poaching. Elephants are not only going to be in captivity for years to come but they need to. Over the last decade their has been great success with elephant breeding techniques and husbandry care. We can bicker amongst ourselves and the activist nut-jobs but that is getting us no where. Personally, if the ele's residing in this outdated enclosures are old (above breeding age) and used to their routine (in most cases for years) why change it? Keep them comfortable. Also, it takes time to raise the money to build and expand. Some Zoochatters seem to think that zoos can just shell out multi-millions to expand, that they have all this money on hand or can get it by making a few phone calls. Believe me its not that easy. I have tried. Just appreciate elephants and realize its not easy or cheap to care for them and even though you are a "sanctuary" you may be doing more harm then good.